1. Field of the Invention
The present invention relates to a portable cleaning machine for cleaning a surface.
2. Background Information
It is know to have cleaning machines for cleaning a surface. One example of a cleaning machine is a carpet extractor that distributes water and detergent cleaning solution to a cleaning surface and substantially simultaneously extracts it along with the dirt on the carpet in a continuous operation. This machine generally uses one or two tanks for holding the cleaning solution and one tank for containing the extracted or recovered dirt and cleaning solution. When using this carpet extractor, the majority of this water is recovered and then discarded. Such an arrangement has several disadvantages. One is that at least two tanks are used which together provide about twice the tank volume that is need to hold the actual volume. Another is that the user has to carry the recovery tank when full to the sink for disposal of the recovered solution and then refill the solution tank(s).
To overcome these disadvantages, the carpet extractor can be designed to recycle the extracted cleaning solution for reuse. This solution would eliminate the additional recovery tank and the disposal of the recovered cleaning solution in the tank several times during the cleaning of the carpet with the carpet extractor. Further, this solution reduces significantly the number of times the user has to stop and refill the solution tank(s). It would also be desirable for such a carpet extractor that has a detergent tank to adjust the amount of detergent in the recycled water or the clean water from a different fluid source, if the extracted water is not reused, so that the ratio of detergent to water is optimized to produce the desired cleaning performance on the carpet.